The duo behind South Park have used the cartoon's latest episode to attack their network for banning them from using an image of the Prophet Muhammad.

Comedy Central prevented Matt Stone and Trey Parker from using the image after the furore caused by a Danish newspaper publishing caricatures of Muhammad.

Instead, Wednesday's episode showed an image of Jesus Christ defecating on President George Bush and the US flag.

Comedy Central said in a statement that it stood by its decision.

"In light of recent world events, we feel we made the right decision," it said.

Scientology protest

The episode was built around the incident, and features the character Kyle trying to persuade an executive at rival network Fox to air an episode of cartoon Family Guy which features an image of Muhammad.

"Either it's all okay, or none of it is," Kyle tells the executive. "Do the right thing."

The executive decides to show the image, but a caption is displayed reading: "Comedy Central have refused to broadcast an image of Muhammad on their network."

It is followed by the images of Christ, President Bush and the flag.

Comedy Central recently cancelled a repeat airing of an episode which mocked Scientology. Singer Isaac Hayes - a Scientologist - quit his role as the Chef character in protest over the episode.

But last month South Park depicted Chef being killed and mourned as somebody whose brains were scrambled by the "Super Adventure Club", which turns its members into paedophiles.

Last week, South Park won US broadcasting's prestigious Peabody prize.

Awards director Horace Newcomb said that by setting out to be offensive, the show "reminds us of the need for being tolerant".